1. Field of the Invention
A brake booster assembly for providing an assistive force in a braking system.
2. Description of the Prior Art
Brake booster assemblies of the type to which the subject invention pertains generally attach to a brake pedal and to a master cylinder for providing a force that is combined with a force applied through the brake pedal to actuate the brakes with the master cylinder. In other words, the brake booster assembly provides an assist to the input force of the master cylinder beyond that provided by a driver's effort in pushing the brake pedal. Many brake booster assemblies use a hollow housing and at least one diaphragm to create pressure chambers within the housing. The pressure chambers are connected to a vacuum source (e.g. an engine intake) using control valves. The diaphragm is attached to a piston which is coupled to the master cylinder and the vacuum pressure provides an assistive force to the input force of the master cylinder as the brake pedal is depressed.
However, smaller engines, supercharging, and emissions requirements in modern vehicles greatly reduce the available vacuum pressure, which necessitates the use of vacuum pumps. Additionally, hybrid and completely electric vehicles may not provide vacuum pressure at all times, or at all. Furthermore, conventional booster assemblies can increase the weight of vehicles due to their complexity and use of large components. Therefore, there remains a significant need for a solution providing an assistive force in a braking system with fewer parts and which may be used on vehicles with little or no available vacuum pressure.